Nitric oxide (NO) is a polypotent regulatory molecule involved in a variety
of activities, such as the modulation of the catalytic activity of cystein
e-containing enzymes. The present study reports the modulation of the HIV-1
reverse transcriptase activity by NO, released by the NO donors 3,3-bis(am
inoethyl)-1-hydroxy-2-oxo-1-triazene (NOC-18), (+/-)-(E)-4-ethyl-2-[(E)-hyd
roxyimino]5-nitro-3-hexenamide (NOR-3), 3-morpholinosydnonimine (SIN-1), 4-
(phenylsulfonyl)-3-((2-(dimethylamino) ethyl)thio)furoxan oxalate (SNO-102)
, and sodium nitroprusside (SNP). NO inhibits dose-dependently the HIV-1 re
verse transcriptase activity, Likely due to oxidation of Cys residue(s). Pr
esent results, representing a new insight into the modulation mechanism of
the HIV-1 reverse transcriptase activity, may be relevant to develop new st
rategies for inhibition of HIV-1 replication. (C) 1999 Academic Press.